88 lines
1.5 KiB
Markdown
88 lines
1.5 KiB
Markdown
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# Functions
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Functions organize your code for reuse. Here's the structure:
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```bash
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function_name() {
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your_commands
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}
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```
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You can also use the `function` keyword for clarity, though it's optional:
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```bash
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function function_name() {
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your_commands
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}
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```
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Example: A simple 'Hello World!' function.
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```bash
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touch hello_function.sh
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```
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Open `hello_function.sh` and add:
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```bash
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#!/usr/bin/env bash
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function hello() {
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echo "Hello World Function!"
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}
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hello # Call the function (no parentheses)
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```
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Save and exit. Make it executable and run:
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```bash
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chmod +x hello_function.sh
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./hello_function.sh
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```
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Functions accept arguments just like scripts.
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```bash
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touch function_args.sh
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```
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Open `function_args.sh` and add:
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```bash
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#!/usr/bin/env bash
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function greet_team() {
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echo "Hello $1!"
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}
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greet_team "Dev Team Six" # Pass argument when calling
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```
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Save and exit. Make it executable and run:
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```bash
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chmod +x function_args.sh
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./function_args.sh
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```
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Document your functions clearly. Include a description, arguments, and expected output/return values.
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```bash
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#######################################
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# Description: Greets a single argument.
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# Globals: None
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# Arguments:
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# $1 - Name/value to greet.
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# Outputs:
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# Prints a greeting to stdout.
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# Returns:
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# 0 on success.
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#######################################
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function greet_example() {
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echo "Greeting: $1"
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}
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```
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Functions are key to building organized and reusable Bash scripts. Master them for efficient automation.
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